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The green links take you to separate pages of information. Know the difference between transcription, translation, and duplication. DNA Duplication: DNA Duplication (or replication) is the process involving the separation (unzipping) the double stranded DNA molecule into two stands, each of which serves as a template to assemble a new complementary strand of DNA. Transcription: DNA to RNA (Happens in the nucleus). Translation: RNA to Proteins (Occurs on Ribosomes in cytoplasm). tRNA binds to codons to link amino acids into polypeptide chains. Bozeman: http://www.youtube.com/watch?v=h3b9ArupXZg Differences between Inducible and Repressible operons. The Inducible Operon is the Lactose Operon. The Repressible Operon is Tryptophan Operon. Lac Operon: When lactose is present in Prokaryotes it needs enzymes to break it down, so the Lac Operon activates RNA Polymerase to make an mRNA strand which will be used to code for the necessary proteins. This is positive control. So to make it simpler when lactose is present, it triggers the making of proteins that process the lactose. Then when the proteins have processed all the lactose, the reaction stops.Gene Regulation Bozeman Video TRP: When lactose is not present Tryptophan stops the RNA Polymerase from making proteins not needed. This is negative control. So to make it simpler, when tryptophan is present, it stops the manufacturing of tryptophan because it doesn't need it. But when it runs out, RNA polymerase can go through and make proteins that produce more tryptophan.Gene Regulation Bozeman Video Bozeman: http://www.youtube.com/watch?feature=player_detailpage&v=3S3ZOmleAj0#t=248s Terminology of heterochromatin, bacteriophage, ligase, DNA polymerase, RNA polymerase. Heterochromatin: Nontranscribed eukaryotic chromatin that is so highly compacted it is visible with a light microscope during interphase. Bacteriophage: A virus that that infects bacteria; also called a phage. Ligase (aka DNA Ligase): A linking enzyme essential for DNA replication; catalyzes the covalent bonding of the 3’ end of a new DNA fragment to the 5’ end of a growing chain. DNA Polymerase: An enzyme that catalyzes the elongation of new DNA at a replication fork by the addition of nucleotides to the existing chain. RNA Polymerase: An enzyme that links together the growing chain of ribonucleotides during transcription. What is a genomic library? It is the whole DNA sequence of an organism chopped into small pieces (with DNA cutting enzymes) and placed into separate plasmids (circular DNA vectors). This collection of plasmids representing the whole genome is called genomic library. It is called library because it contains pieces of whole genetic information of an organism separately kept in small "booklets". When is PCR used? Polymerase Chain Reaction make billions of copies of a particular DNA sequence. It is used to analyze DNA and enables scientists to analyze DNA they previously could not. Explain the membrane potential of a neuron. Membrane potential is the difference in voltage between the inside and outside of a cells membrane. The membrane potential (resting potential) of a neuron is around -70 millivolts. While at resting potential, it is polarized, and its ion channels are closed, letting fewer sodium ions into the membrane and fewer potassium ions to the outside. Neurotransmission stimulates the neuron, depolarizing it, and its membrane potential becomes slightly more positive. When depolarizing, it may reach its threshold (about 10 millivolts more positive than negative) the neuron reaches its action potential by completely depolarizing the membrane. Also, when it depolarizes, it opens up and allows more sodium in of the membrane and makes the membrane more positive. Once enough sodium has come into the membrane and the potential is more positive than the outside, the sodium channels close, allowing less sodium. Then the potassium channels open, to let sodium ions out, to return the membranes potential to normal, called repolarization, then re-closing the sodium channels. Before it returns to normal, it undergoes a refractory stage, where it is more negative than normal, and cannot fire another action potential. Once at resting state, the excess sodium and potassium slowly diffuse from the membrane to reach equilibrium in the membrane. The membrane is now ready to perform another action potential. Negative values indicate that the neuron is more negative on the inside. Remember: The value of the membrane potential is measured outside minus inside.Human Physiology - Neurons & the Nervous System More Information: http://people.eku.edu/ritchisong/301notes2.htm What occurs during an action potential? Be able to describe it from a graph. Action potential is a rapid change in the membrane potential of an excitable cell, caused by stimulus-triggered, selective openings and closings of voltage-sensitive gates in sodium and potassium ions. Membrane potential goes from resting potential to a positive value in a very short time; the stimulus causes the sodium channels to open and sodium diffuses rapidly into the cell; positively-charged potassium ions diffuse out. Understand Bowman’s capsule and the pathway through the nepheron. Bowman's capsule filters blood to be recirculated through the body. Nitrogenous waste is turned to ureic acid, which is expelled from the body. What is population density? A population density is the total number of individuals per area or volume occupied. Example: 100 buffalo/km^2 How is the growth rate of a population expressed? dN/dT = B - D dN/dT is the rate B''' is births '''D is deaths Differentiate between a logistic and a exponential growth curve. Logistic Growth: 'A model describing population growth that levels off as a population size approaches carrying capacity. '''Exponential Growth: '''The geometric increase of a population as it grows in an ideal, unlimited environment. Differentiate between density independent and density dependent factors. A density-dependent factor is one where the effect of the factor on the size of the population depends upon the original density or size of the population. A disease is a good example of a density-dependent factor. If a population is dense and the individuals live close together, then each individual will have a higher probability of catching the disease than if the individuals had been living farther apart. Not only will a greater number of individuals be affected, but, more importantly, a greater proportion of the population will be affected if they are living close together. For example, bird populations are often regulated more by this type of regulation. ''Example: In general, density-dependent factors are biological factors, such as diseases, parasites, competition, and predation. A density-independent factor is one where the effect of the factor on the size of the population is independent of and does NOT depend upon the original density or size of the population. The effect of weather is an example of a density-independent factor. A severe storm and flood coming through an area can just as easily wipe out a large population as a small one. Another example would be a harmful pollutant put into the environment, e.g., a stream. The probability of that harmful substance at some concentration killing an individual would not change depending on the size of the population. For example, populations of small mammals are often regulated more by this type of regulation. Example: In general, density-independent factors are physical factors, such as weather factors (e.g., severe winter) or the presence of harmful chemicals. What adaptations have helped flowering plants survive and thrive? Supporting structures: stems, roots, etc.. Anchoring structures: roots/ rhizoids Vascular system (xylem and phloem) Regulation of gas exchange through the stoma Reproductive strategies for dry conditions Diagram a typical neuron. Differentiate between specific and nonspecific immune responses. '''Specific immune response: lymphocytes(white blood cells), macrophages, T Cells, Memory B cells Nonspecific immune response: skin, hair, tears, etc. What is the respiratory pigment and how does its structure aid its function? Respiratory pigment: '''Hemoglobin is the respiratory pigment and its four subnits allow for carrying of oxygen. Hemoglobin has two alpha subunits and two beta subunits. Amino acids hold the iron in the center of the hemoglobin. Oxygen binds to the iron in hemoglobin. Understand the difference between Type I, II, and III survivorship curves. Type I: Few offspring, but take care of them. Some examples include humans and elephants. Type I is K-Selection. Type II: Mesh between Type I and III. Type III: Many offspring, so not all can be taken care of. Some examples are spiders and plants. Type III is R-Selection. What are the benefits of coevolution? http://www.bio.miami.edu/ecosummer/lectures/lec_coevolution.html Biological coevolution is the evolutionary change of one species triggered by interaction with another species. Benefits: allows species to evolve to have a better chance of survival. http://www.youtube.com/watch?v=QDVbt2qQRqs - Bozeman Co-evolution video Differentiate between K-selection and r-selection. '''K-Selection: The concept that in certain (k-selected) populations, life history is centered around producing relatively few offspring to have a good chance of survival. R-Selection: The concept that in certain (r-selected) populations, a high reproductive rate is the chief determinant of life history. What factors affect species richness in an ecosystem? The more diversity in an ecosystem, and the greater the number of species, the more likely an ecosystem will be stable. Food, temperature, resources, climate, and availability of water all affect species richness. References